Apparatus for distributing pulverized fuel to burners



June 1932. F. D. KIRTLAND ET AL 5 APPARATUS FOR DISTRIBUTING PULVERIZEDFUEL TO BURNERS Filed Jan 23, 1929 2 Sheets- Sheet 1 June '7, 1932.

F. D. KIRTLAND ET AL 1,361,535

APPARATUS FOR DISTRIBUTING PULVERIZED FUEL TO BURNERS Filed Jan. 23.1929 2 Sheets-Sheet 2 h i :l 1 .9 6'-- I? 1 ll ii i: II EI M )A Ik 1 u[lg =1: n: 1O 1Z7 1 l ii WM Patented June 7, 1932 UNITED STATES ATENTOFFICE FRED D. KIRTLAND, OF GEBMANT'OWN, JOSEPH J. BROSHEK, OFPHILADELPHIA, AND RALPH C. BRIERLY, 0F NABB'ERTH, PENNSYLVANIA, ANDJOSEPH S. EVANS, OF SCHENECTADY, NEW YORK, ASSIGNORS TO PEABOD'YENGINEERING CORPORATION,

A CORPORATION OF NEW YORK APPARATUS FOR DISTRIBUTING PULVERIZED FUEL TOBUBNERS Application filed January 23, 1929. Serial No. 334,468.

This invention is an improvement in apparatus for distributingpulverized fuel to burners.

Pulverized fuel, such as crushed coal, is carried to the burners by anair blast, and however uniformly distributed throughout the column ofair, and however well balanced and homogeneous the mixture at thebeginning, it does not remain so during its travel. Any alteration ofdirection in the travel of the column tends to cause the fuel particlesto group themselves unequally in the stream.

In the utilization of such fuel, by means of carrier air, it isessential that the fuel be uniformly distributed throughout the columnof air, so that the burner or burners may supply a substantially uniformand substantially constant heat.

When the delivery is to a plurality of burners, it is of the utmostimportance that an equal supply be furnished to each burner, and it isessential that the column of carrier air leaving the grinder orpulverizer, and carrying the total supply of fuel, be divided intostreams, each supplying a uniform mixture to the individual burner.

One of the primary objects of the present invention is the provision ofapparatus for distributing pulverized fuel to burners providing for auniform homogeneous and well balanced condition of the mixture of fueland air at the point where the mixture is delivered, either to a burner,or to a plurality of individual burners.

With the foregoing and other objects in view the invention consists inthe construction and novel combination of parts fully describedhereinafter, illustrated in the accompanying drawings, and pointed outin the claims appended hereto, it being understood that various changesin the form, proportion, size and minor details of construction withinthe scope of the claims, may be resorted to without departing from thespirit of the invention.

In the drawings forming a part hereof Fig. 1 is a view of one embodimentof the invention showing the casing in longitudinal section and thedistributor in elevation.

F ig. 2 is a bottom plan view of the distributer element.

Fig. 3 is a plan view of one of the blades of the topmost assembly.

Figs. 4:, 5, 6 and 7 are views similar to Fig. 1, showing alternateforms of the apparatus.

In the embodiment of the invention shown in Figs. 1 to 3 inclusive, asection 1 of the supply conduit for the mixture is shown, and a mushroomshaped chamber 2 is connected with the outlet end of the conduit, bymeans of lapping flanges 1a on the conduit section, and 2a on thechamber. The conduit 1 has a. flange la at each end, the flanges beingrings, in the present instance, threaded on the ends of the conduitsection.

The chamber 2 flares outwardly from the end of the conduit section, andis provided with a plurality of ports, with each of which is connected abranch line 3. Each of these branch lines is designed to connect withseparate furnaces, burners, or other apparatus, and it will be noticedthat the branch connections 3 are arranged at acute angles to the axisof the conduit section, and as nearly in line with the flow through theconduit section as possible. That is, the arrangement is such that thechange of direction of the air column flowing through the conduit is asslight as possible.

A shaft 5 is journaled at the axis of the casing, in bearings 6, one ofwhich is at the outer end of the chamber 2, and the other in a spider 8extending radially into the conduit at the inlet end of the section 1. Astufling box 7 is provided at each bearing, and any suitable operatingmeans may be connected with the shaft to rotate the same. lhe stuflingboxes prevent the entrance of the particles of fuel to the bearings, andprevent the escape of such particles from the chamber 2.

Three sets of blades are carried by the shaft 5, the said sets beingindicated at 9, 10 and 11. In the present instance, the blades of thesets 10 and 11 are shown as plane, with the wide dimension parallel withthe axis of the shaft, and the blades of the set 10 are 7 tangential tothe shaft, while those of the set in Fig. 2. It will be apparent,however, that the blades 10 and 11 may have any other desired contour.

Whether the blades 10 and 11 have the contour shown, or another contour,it is preferable that the blades of the set 9 be curved as shown inFigs. 1 to 3 inclusive. The blades 9 also are of greater width than theblades of either of the other sets, and the outer edge of each blade 9,that is, the edge adjacent to the branch lines 3 is beveled somewhat, sothat with the curvature of the blade, the figure described by the upperedges of the blades corresponds substantially with the outer wall of thechamber 2.

A cone shaped element 14 is secured to the shaft between blades 9 andthe outer end of the casing 2, the small end of the member beingadjacent the said blades. This member is designed to prevent eddying atthe point where there might be a region of zero pressure, due to thecentrifuging action of the distributer, and to assist in perfecting theuniformity of dissemination at this point. The surface of the member maybe smooth as shown, fluted, or spirally threaded, if de sired.

It will be noticed referring to Fig. 1, that the arrangement of themember 14, and the arrangemment of the blades 9, provide for an annularpassage within the chamber 2 of a width substantially equal to thediameter of any branch 3, and with a capacity greaterthan the aggregateof the capacities of the said branches. This provides for an unimpededflow from the conduit section to the branches, enabling some expansionof the mixture stream as it leaves the conduit section for distributionto the branches.

The embodiments of the invention shown in Figs. 4 and 5, are similarinall respects to that shown in Fig. l, with the exception of the coneshaped member, which in both embodiments is of hollow or chamberedmetal, being indicated at 15 in Fig. 4, and at 16 in Fig. 5. In Fig. 4,it is composed of two frustums of cones placed base to base. In Fig. 5,the member 16 has the contour of the frustum of a cone and the segmentof a sphere seated base to base. I

In the embodiment shown in Figs. 6 and 7 the cone shaped member isomitted. In Fig. 6, the element 17 corresponding to the chamber 2 ofFig. 1 is dome shaped and does not flare as in Fig. 1. The blades 19 ofthe outermost set, which correspond to the blades 9 of Fig. 1, arearranged partly within the dome, and the outer edges thereof are curvedto correspond to the curvature of the dome. In Fig. 7, the element 18,corresponding to the element 2 of Fi 1, is a conical cap, and notflaring as is the element 2. The blades 20 of the uppermost set arearranged within the cap 18, and the outer edges of the blades are 11 ina clockwise direction, while the blades.

10 precede the blades 9. Thus the blades of each set supplement theoperation of the blades of the other sets. Each set of blades displacesthe air current angularly, imparting to the current a swirlingor-spi-ral motion, and the blades 9 of the last set accelerate thisswirling or spiral motion due to their curvature.

In the embodiment shown in Figs. 14, the shaft and blades are rotated ina clockwise direction, but in the other embodiments the shaft may berotated in either direction.

What is claimed as new is p 1. In combination with a conduit for airladen with pulverized fuel, a distributor including a shaft providedwith a plurality of sets of blades, the sets being spaced apart fromeach other longitudinally of the shaft, whereby the blades of each setcomplement the blades of the other sets, the blades of the last set bentto impart an accelerated spiral motion to the air, means to rotate saidshaft, a chamber connected with the outer end of the conduit, and aplurality of branch lines leading from said chamber.

2. In combination with a conduit for air laden with pulverized fuel andprovided at the end with a plurality of outlets with axes inclinedslightly outward from the axis of the conduit, a distributor including ashaft journaled to rotate at the axis of the conduit, and provided witha plurality of sets of blades, the sets being spaced apart from eachother longitudinally of the shaft, and the blades of the last set bentto impart an ac celerated spiral motion to the air.

3. In combination with a conduit for air laden with pulverized fuel andprovided with a flaring outlet having connections for a plurality ofbranch conduits, a distributor including a shaft journaled to rotate atthe axis of the conduit and provided with a plurality of sets of blades,the sets being spaced apart from each other longitudinally of the shaft,and the last set being spaced from the end of the outlet by asubstantially conical member on the shaft, the base of said member beingat the end between the connections for the branches.

4. In combination with a conduit for air laden with pulverized fuel andprovided at the end with a plurality of outlets with axes incliningslightly outward from the axis Bf the conduit, a distributer including ashaft journaled to rotate at the axis of the conduit, and provided witha plurality of sets of blades, the sets being spaced apart from eachother longitudinally of the shaft, and the blades of the last set bentto impart an accelerated spiral motion to the air, the blades of thelastset being spaced apart from the end of the conduit by afrusto-conical element arranged on the shaft with its base at the end ofthe conduit and between the outlets.

5. Apparatus for distributing pulverized fuel to burners comprising aconduit having a dome at one end with a plurality of outlets with axesinclined to the axis of the conduit, a shaft journaled to rotate in theconduit at the axis thereof, a plurality of sets of blades carried bysaid shaft, the sets being spaced apart from each other longitudinallyof the shaft, and the blades of the uppermost set extending partly intothe conduit and into the dome and having their top edges conforming tothe shape of the top of the dome.

Signed at Philadelphia, in the county of Philadelphia, and State ofPennsylvania, this 22nd day of October, A. D. 1928.

FRED D. KIRTLAND. JOSEPH J. BROSHEK. 25 RALPH C. BRIERLY.

Signed at San Pedro, California, in the county of Los Angeles and Stateof California, this 10th day of January, A. D. 1929.

JOSEPH S. EVANS.

